mikrotik mAP Lite as a fallback internet connection

After watching this video: Using a Phone Hotspot as a Backup WAN Connection

I wanted to try that so I ordered a “MikroTik RBMAPL-2ND”, aka “mAP Lite” for 34,47 EUR (incl shipping) and set it up according to the video.

Transcript of changed settings below.

A first test with a laptop connected via ethernet to the mAP and the mAP to the phone hotspot was successful. After that it was connected to the FritzBox 7530 AX's LAN3 port and configured as the “fallback protection” (Ausfallschutz) after 3 minutes, reverting after 30 minutes. This works fine, except the FritzBox does not automatically revert back earlier if DSL is back. So if you switch off the hotspot the routing is broken until you deactivate the fallback protection. Still ok though. AVM post. This needs fritzOS 8.20.

# Connect via wifi to 192.168.88.1

Bridge -> Ports -> Add new
	defconf: Interface ether1
		Click Apply/OK
	
Interfaces -> Interface List
	WAN/ether1
		Click Disable
	
IP -> DHCP Client -> DHCP Client
	defconf: ether1
		Click Disable

# Connect via ethernet to 192.168.88.1

Bridge -> Ports
	bridge
		Remove wlan1

Interfaces -> Interface List
	WAN
		Change to wlan1
		Click Enable

Wireless -> Wireless
	Wireless -> Mode
		Change ap-bridge to station
		(Leave Security Profile: default)
	
Wireless -> Security Profiles
	default
		Change Mode: none to "dynamic keys"
		Change Auth to "WPA2 PSK"
		Change WPA2 PSK to <KEY>
		Change Frequency to "auto"
		
Wireless -> Wireless
		Change SSID to <SSID>
		
IP -> DHCP Client -> DHCP Client
	defconf
		Change ether1 to wlan1

The mAP Lite stays on 192.168.88.1 for now, in case of fallback the FritzBox will get an IP via DHCP in the 192.168.88.0/24 range.